// 需要给speek 和 identify 显示传入一个对象
// function speak(p) {
//     var greeting = "Hello, I am " + " " + identify(p) + ".";
//     console.log(greeting);
// }
// var Person = { name: "John" };

// function identify(p) {
//     return p.name.toUpperCase();
// }

// speak(Person);

function speak() {
    var greeting = "Hello, I am " + " " + identify(this) + ".";
    console.log(greeting);
}
var Person = { name: "John" };

function identify(p) {
    return p.name.toUpperCase();
}
speak.call(Person)